1. Field
This disclosure relates generally to apparatus and methods for providing optimized signaling for high-speed wireless communication. More particularly, the disclosure relates to transmit-response timing for relay operation in wireless communication.
2. General Background
Wireless communication systems are widely deployed to provide various types of communication content such as voice, data, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., bandwidth and transmit power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, 3GPP Long Tenn Evolution (LTE) systems, and orthogonal frequency division multiple access (OFDMA) systems.
Generally, a wireless multiple-access communication system may simultaneously support communication for multiple wireless terminals. Each terminal communicates with one or more base stations via transmissions on the forward and reverse links. The forward link (or downlink) refers to the communication link from the base stations to the terminals, and the reverse link (or uplink) refers to the communication link from the terminals to the base stations. This communication link may be established via a single-in-single-out, multiple-in-signal-out or a multiple-in-multiple-out (MIMO) system.
In general multiple access wireless communications are managed at least in part from a serving network as a controller or arbiter of wireless traffic. The serving network may send control information to user equipment, assigning particular wireless resources to different access terminals, managing uplink and downlink interference, coordinating MIMO transmissions among neighboring base stations, sharing network load among available base stations, and so on. In essence, the serving network acts as a central planner for managing disparate wireless communications, to ensure consistency for high quality traffic and moderate reliability for best effort traffic.
As networks expand in geography and both networks and user equipment evolve in electronic capabilities, network management takes on additional complexity. Backward compatibility is a particular constraint that may potentially add much design complexity to network planning and deployment. New electronic capabilities, both on network equipment and user equipment, enable new wireless features, services, and performance for wireless communication. However, these new capabilities may often require changes to standardized mechanisms for conducting wireless communication. These changes may often preclude equipment designed on a previous standard from employing a new standard, however. Particularly for user equipment, significant changes in standards may render millions of mobile phones, computer accessories, and so on, that employ wireless communications obsolete. Backward compatibility, on the other hand, ensures support for legacy equipment in conjunction with new standards designed around new electronic features and capabilities.
Perpetually porting older standards into newer systems may lead to convoluted wireless communication architectures, however, based on fractured or fragmented rule sets for different types of electronic equipment. Accordingly, new research in wireless communications is typically directed at accommodating new technology without prejudicing equipment that operates the technology or legacy devices that employ them. This concept typically applies for radio access network infrastructure (e.g., base stations, relay stations, repeater stations, base station controllers, mobile switching centers, and so on), core network infrastructure (e.g., location registers, billing and charging servers, subscription servers, customer support infrastructure, etc.), as well user equipment itself (e.g., mobile phones, personal digital assistants, smart phones, and the like). Wireless communication standards groups (e.g., 3GPP, 3GPP2) are typically charged with keeping these concerns in mind when adopting new standards for access networks, core networks and user equipment, based on new and emerging electronic technologies.